Department of Chemistry, Rural Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2012;47(3):497-505. doi: 10.1080/10934529.2012.640249.
Chromatographic procedures such as solid phase extraction and high performance liquid chromatography coupled with a fluorescence detector (SPE-HPLC-FLD), were carried out to determine the concentrations of the surfactant nonylphenol ethoxylate (9 ethylene oxide units, NP9EO) and its biodegradation product, 4-nonylphenol (NP), in samples collected from the wastewater treatment system at the University Hospital (HUSM) of the Federal University of Santa Maria. The results showed a high concentration of NP9EO in all the collected samples (0.075 - 4.12 mg L(-1)) and an almost complete absence of NP. In addition, electrocoagulation (EC) of NP9EO was carried out in aqueous solution and in the HUSM effluent. A NP9EO removal rate of 95 % was achieved from the aqueous solution, following a pseudo-first-order kinetics. Through LC-MS measurements in aqueous solutions, it was possible to determine the formation of short-chain nonylphenol ethoxylate (NPEO), such as nonyl-phenoxy acetic acid (NP1EC), after 30 min of EC. In the case of the HUSM wastewater, the NP9EO removal was 89 %, and the chemical oxygen demand (COD) abatement was 26 %. A respirometric test was conducted to measure the increase of biodegradability during the EC and the aqueous samples were found to be less readily biodegradable before the 30-min period of electrocoagulation than after it had been completed.
采用固相萃取-高效液相色谱-荧光检测（SPE-HPLC-FLD）等色谱程序，对从圣玛丽亚联邦大学医院（HUSM）污水处理系统采集的样品中的表面活性剂壬基酚聚氧乙烯醚（9 个环氧乙烷单元，NP9EO）及其生物降解产物 4-壬基酚（NP）的浓度进行了测定。结果表明，所有采集的样品中 NP9EO 的浓度都很高（0.075-4.12mg/L），几乎没有 NP。此外，在水溶液中和 HUSM 废水中进行了 NP9EO 的电絮凝（EC）实验。在水溶液中，NP9EO 的去除率达到 95%，符合准一级动力学。通过在水溶液中的 LC-MS 测量，在 EC 后 30 分钟，有可能确定短链壬基酚聚氧乙烯醚（NPEO）的形成，如壬基酚氧乙酸（NP1EC）。对于 HUSM 废水，NP9EO 的去除率为 89%，化学需氧量（COD）的去除率为 26%。进行了呼吸计量测试以测量 EC 过程中生物降解性的增加，结果发现，在电絮凝 30 分钟之前，水溶液的生物降解性比电絮凝完成后更差。
